1. Field of the Invention
The present invention relates to a compressor which is used for a refrigerator or an air conditioner and which has an oil pump for lubricating a compression element.
2. Description of Related Art
A conventional vertical-type scroll compressor is configured so that the oil in an oil reservoir 101 located at the bottom of the compressor is supplied to a scroll compression element, which is mounted on one end of a rotary shaft, and bearings via an oil pump 100 mounted on the other end of the rotary shaft as shown in FIG. 14.
When such a compressor is installed horizontally, the interior of the compressor is divided into hermetically sealed chambers 201 and 202 by a partitioner 205, the hermetically sealed chamber 202 serving as an oil reservoir as illustrated in FIG. 15. An oil pump 400 is constituted by two pumps: one pump sends the oil, which gathers at the bottom in the hermetically sealed chamber 201 after lubricating the scroll compression element and bearings, to the hermetically sealed chamber 202 via a pipe 203; and the other pump supplies the oil in the hermetically sealed chamber 202 to the scroll compression element and the bearings via a lubricating bore 414 of a rotary shaft 410.
The oil pump 400 in FIG. 16 is constructed by: a housing 404 which has a cylinder 415, an inlet 402, and an outlet 403; a cover 401 for closing the opening of the cylinder 415 of the housing 404; a housing 407 which has a cylinder 416 and an inlet 409; covers 411 and 412 for closing the opening of the cylinder 416 of the housing 407; a rotor 405 which is rotated in the cylinder 415 by the rotary shaft 410; a rotor 408 which rotates in the cylinder 416; and a partitioner 406 which provides a partition between the cylinder 415 and the cylinder 416.
The pump for sending the oil in the hermetically sealed chamber 201 to the hermetically sealed chamber 202 via the pipe 203, and the pump for supplying the oil in the hermetically sealed chamber 202 to the scroll compression element and the bearings via the lubricating bore 414 of the rotary shaft 410 are configured as described above.
If the compressor has a hermetically sealed vessel filled with low pressure gas, then the inlet of the hermetically sealed chamber for reserving oil or the inlet of the oil pump is provided at the bottom of the hermetically sealed vessel.
If the compressor has a hermetically sealed vessel filled with high pressure gas, then the inlet of the oil pump is provided in the hermetically sealed chamber, which has lower pressure, of the hermetically sealed vessel because the oil gathers in a place in the vessel where the pressure is lower.
In the case of the horizontal-type scroll compressor having the conventional structure described above, if the hermetically sealed vessel thereof is filled with the low pressure gas, then the oil spreads all over the internal surface of the hermetically sealed vessel. This has been posing a problem in that, if the compressor tilts or foams, then insufficient lubrication is apt to occur and more oil is undesirably discharged.
If the hermetically sealed vessel of the compressor is filled with high pressure gas, then the area of lower pressure is located near the discharge pipe which provides the outlet of the discharged gas of the compressor. Hence, the oil tends to be discharged together with the discharged gas, posing a problem of an increased amount of discharged oil.
Further, the horizontal-type scroll compressor requires two pumps, one for sending the oil from the hermetically sealed chamber 201 to the hermetically sealed chamber 202, and the other for feeding the oil from the hermetically sealed chamber 202 to the scroll compression element and the bearings as described above.
For this reason, the number of components is doubled, including the cylinders 404, 407, the rotors 405, 408, and the covers 401, 406, 411, 412, resulting in higher cost.